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(No Model.) a Sheets-Sheet 1..

J. H. HUNTER. ELECTRIC DANGER ALARM FOR RAILWAY BLOCK SIGNALS.

No. 417,188. Patented Dec. 10, 1889..

Fig-1 I INVENTOR:

By "6 i;

Attorney.

(No Model.) 3 Sheets-Sheet 2.

J. H. HUNTER. ELECTRIC DANGER ALARM FOR RAILWAY BLOCK SIGNALS.

No. 417,188. Patented Dec. 10, 1889.

INVENTUH:

N, PETERS, PIIOIO'UIHEQNPHM. Washington D, C,

(No Model.) 3 Sheets-Sheet 3.

J. H. HUNTER.

ELECTRIC DANGER ALARM FOR RAILWAY BLOCK SIGNALS. N0. 417,188. Patented Dec. 10, 1889.

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UNITED STATES PATENT- OFFICE.

JAMES H. HUNTER, OF NEWV YORK, N. Y.

ELECTRIC DANGER-ALARM FOR RAILWAY BLOCK-SIGNALS.

SPECIFICATION forming part of Letters Patent No.41'7,188, dated December 10, 1889.

Original application filed February 19, 1389, Serial No. 300,475. Divided and this application filed August 31, 1889. Serial No.

322,553- (No model.)

To a whmn it 727M111] concern.-

Begit :known that I, JAMES H. HUNTER, a subject of the Queen of Great Britain, and a resident of the city, county, and State of New York, have invented certain Improvements in Electric Danger-Alarms for Railway Block Signals, of which the following is a specification.

My invention relates to that class of danger-alarms for electric blocksignal systems on railways wherein asignal is sounded or displayed in the cab of the locomotive whenever there is danger aheadas, for example, when there is a train in the same block. These danger-alarm systems have employed suitable electrical conductors connecting the magnets of circuit breakers or relays at points which divide the road up into blocks or sections, and also at other points where needed.

In operating such systems an electriccurrent generator, usually a dynamo run by a special engine, is mounted on the locomotive, said generator being in a normally-closed circuit on the locomotive.

In a pending application of mine, Serial No. 300,475, of which this application is a division, mechanical devices are shown whereby the normally-closed circuit on the locomotive is'broken when the locomotive enters a block, and a partial circuit on the locomotive, including the generator, is connected with a track or line circuit or partial circuit controlled by a relay, whereby, if the said relay is set to danger, the newly-formed circuit will be broken or incomplete and a dangersignal will be given to the engineer; but if the relay be set to safety the newly-formed circuit will be complete or closed and the engineer will receive no signal. It has been found by experience that the electro-motive force generated by the means usually employed will not remain constant, and when a considerable external resistance is shunted into the circuit by the connecting of the partial circuit on the locomotive with a comparatively long line or track circuit the electromagnet controlling or operating the dangersignal is rendered very unreliable. To obviate this defect is the purpose of my present invention, which consists in introducing into the circuit on the locomotive a device which I call a distributer, comprising a peculiar circuit breaker and closer and an external resistance equal to the resistance of the longest conductor in the line or track circuit.

My invention will be fully described hereinafter, and its novel features carefully delined in the claims.

In the accompanying drawings, which serve to illustrate my invention, I have shown a mechanical device for breaking and closing the shunt circuit on the locomotive, constructed like or similar to that described and claimed in my said pending application, Serial No. 300,475; but this feature is merely shown for purposes of illustration in connection with my distributer. Any means whatever may be employed for effecting the obj ect accomplished by this mechanical device.

In the said drawings, Figure 1 is a side elevation of a locomotive provided with my improvements, and Fig. 2 is a view showing every part of the device with all the circuits. This view being simply for explanation, the proper proportions of the parts and their relative positions in practice have not been maintained. Figs. 8 and 4 are views, on a small scale, showing the arrangement of the relays and line-wires at two adjacent block-stations along the line of railway.

Referring to the drawings, 0050' are the two track-rails of a line of railway, and X is a locomotive thereon.

X is the cab of the locomotive, and X the pilot thereof.

G is the electric-current generator, which I usually mount on the pilot of the locomotive in a suitable box or casing, and B is the distributor as awhole, which is usually mounted in the same box with the generator.

Sg is the dangersignal, usually mounted in the cab of the locomotive. This signal may be an ordinary electric bell in a normallyopen circuit.

R represents as a whole one of the relays or circuit-breaking devices along the line. Mechanically this device consists of asafety electro-magnet S, a danger electro-magnet D, an armature-lever Z, carrying the armature for both magnets, and a contact piece or screw m. These parts are essentials, but they may be arranged in various ways.

' brush 6 form the shunt.

The distribute-r B, Fig. 2, consists mechanically of a suitable base 011 which is mounted a metal post g, in the top of which is mounted a metal rocking lever 71 bearing two armatures t' and '2 which are adapted to be brought alternately by the rocking of said lever into electrical contact, respectively, with the cores of two electroanagnets C and C, mounted on the same base with the post There is a carbon or other resistance at in circuit with the coils of the magnet C. These parts may of course be arranged in any satisfactory way.

In order to make the functions and operation of the distributor fully understood, I will explain the construction of the mechanical circuit-controlling device herein illustrated, promising that the purpose of this device is to break the normally-closed shuntcircuit on the locomotive at the point where the engineer is to receive a danger-signal, if there be any danger, and at the point where the locomotive sets the relays to danger and safety, respectively, and to connect the partial circuit on the locomotive with the partial circuiton the line. Between the track-rails is placed an insulated inclined contact-rail A. This rail is placed at the receiving-point where the engineer is to receive the signal of danger. Under the locomotive is mounted a slide (1, having in its lower end a wheel a to contact with and roll on the inclined rail A. When wheel a is not in con- .tact with rail A, an insulated brush c forms a metallic contact with the slide Z); but when the slide 79 is raised by. contact of wheel a with rail A a plate f, of insulating material, on the slide is brought under brush 6. Normally the brush 0 is in electrical contact with the slide 1). a

I will now explain the circuits with reference to Fig. 2. I and N represent the binding-posts at the positive and negative poles, respectively, of the generator. The current flows from binding-post P through the wire l to the post g of the distributor l3, thence through the right-hand end of the vibrating or rocking lever h, through the armature i on said lever, through the core of the electro-magnet 0, through wire 2, through the coil of the magnet C and the wire 3 to a binding-post j, and thence it flows through the wire 4 to the brush 6, thence to the slide Z), and thence through the wire 5 to the binding-post N at the negative pole of the generator. The circuit described is normally closed and is wholly confined to the locomotive. The wire 4: and

Now, when the locomotive enters a block the wheel a rolls up the incline on the rail A, the slide 1) is moved upward, and this breaks the shunt-circuit I have just described by reason of the plate f of insulating material being brought under the brush e. Instead of flowingthrough the wire at from the binding-post j, the current flows from said binding-post through a wire 6 to a wheel 79 of the locomotive, thence to the trackrail cc, and thence byawire 7 to the armaturelever Z of the relay R, thence to the contactscrew m of the relay, thence by a wire 8 to the contact-rail A, and thence through the wheel a, the slide 1), and the wire 5 back to the generator. Thus it will be seen that if the armature-lever l of the relay is in contact with the screw m, as seen in Fig. 2, the circuit will remain closed. In this case the engineer will receive no signal. I denominate the magnet S of the relay R the safetymagnet, as it serves to set the relay to safety by closing the circuit. On the other hand, the magnet D of the relay breaks the circuit and sets the relay to danger, and I therefore denominate it the danger-magnet.

By reference to Fig. 2 it will be seen that the current flowing from the binding-post P to the post g of the distributor B is divided and a portion of the current flows through a wire 9, thence through the coil of the magnet C, thence through a wire 10 to the external resistance or, which is equal to the external resistance of the longest conductor on the line,

and thence through a wire 11 back to the generator. The circuit through the coil of magnet G is always closed, and consequently the magnet is always excited; but owing to the external resistance a the magnet O is less powerful than the magnet O, which is also in a state of excitation normally.

If the relay for any reason is set to danger, the locomotive reaches the receiving- .pointand the contact between its lever Z and screw m is broken, when the wheel a rolls up on rail A and breaks the locomotive-circuit by moving the plate f up under the brush 6. The current cannot flow through wires 7 and 8 because of the break at the relay. Consequently the magnet O is demagnetized, and the magnet C, which is always excited, will attract its armature 2' into contact with its core, thus closing the normally-open circuit containing the signalor bell So. The current flows now from the binding-post P through wire Z, )ost g, rocking lever h, armature t", the core of the magnet U, and the wire 12 to the bell Sg in the cab, and thence back through the wire 13 to the generator. The engineer will thus receive a signal of danger by the ringing of the bell.

In order to stop the bell from ringing and to again close the main circuit through the core of magnet O, a switch or circuit-closer is employed convenient to the engineer, whereby he can, by simply closing a restoringcircuit, send a current through the coil of magnet C. The effect of this is to rock the lever h of the distributer, and thus break the bell-circuit and restore the main circuit by the contact of the armature a} with the core of the magnet 0. S20 is this switch, mounted in the cab of the locomotive. It may as well be an ordinary push-button of the kind known to all electricians; or, indeed, any spring-contact device that will automatically break the restoring circuit when the engineer removes the pressure may be employed equally well. I have shown an ordinary lever-switch merely for convenience of illustration. If such a switch were used, the engineer might inadvertentlyleave the restoring-circuit unbroken. WV hen the engineer closes this switch, the current flows from binding-post P through a wire 14 to the switch or button 'Sw, thence by a wire 15 to and through the coil of magnet C, thence by the wires 3 and 4 to the brush 6, and thence through the wire 5 to the bindingpost N. It will be observed that by the time the engineer shall have had an opportunity to manipulate the switch Sw the wheel a on the locomotive will have again descended after having passed over the inclined rail A, whereby the brush 6 will have been again brought into electrical contact with slide 19. The 10- comotive, having passed the receiving-point and having received no danger-signal, advances into the block to the relay-actuating point or transmitting-point, which will usually be a short distance in advance of the receiving-point.

In Figs. 3 and 4 I have shown a block C and parts of two blocks B andD and stations 0 and 00, the former at the entrance to block O and the latter at the entrance to block D. The locomotive in Fig. 3 is shown as at the receiving-point at station 0 and ,as just entering block C, and the locomotive in .Fig. 4 is shown as having entered block 0 and reached the transmitting-point.

Figs. 2, 3, and 4 may be examined together in order to understand the mode of transmitting back to the preceding stat-ion.

On the line of railway at the transmittingpoint is placed a second contact-rail A, which is exactly like rail A. I have given it a different reference-letter for distinction only. In Fig. 2 this rail is diagraphically represented as situated just below rail A. \Vhen the locomotive reaches this transmitting-point, the wheel Ct rolls up on rail A, and thus simultancously breaks the locomotive shuntcircuit (through the brush 6) and shunts into the circuit with the generator G the coil of the danger-magnet Do]? the relay at station 0 and the safety-magnet S of the relay at the next station behind-that is, at the entrance to the block 13. The current flows (see Fig. 2) from the binding-post P through lg ht 2 O 3 6 k to the rail 00, thence by a Wire 15 to the danger-magnet D at station 0 through the coil of this magnet, thence (see Figs. 3 and 4) back to the preceding station (represented diagraphically by dotted lines in Fig. 2) through the coil of that magnet, and thence forward by a wire or other conductor 17 to the contact-r+ail A, thence through the wheel a, slide 1), and wire 5 to the other pole of the generator. The ettect of this will be to excite the electro-magnets thus put in circuit and to setthe relay at station 0 to danger and the relay at the preceding station to safety. WVhen the locomotive reaches the station '00 ahead, it sets the relay at this station to danger and the relay at station 0 to safety. 7 hen thelocomotive reaches the transmitting-point, (at rail A,) the external resistance in the circuit with the coil of the magnet C of the distributer B will be very considerable. Consequently the attractive power of this magnet, tending to preserve the contact between its core and armature, will be correspondingly weakened; hence, as the magnet G is always excited, I put an external resistance or in circuit with the coil of the magnet C equal to the greatest resistance that there may be in the transmitting-circuit. Otherwise the magnet O would overcome magnet 0 when the transmitting-pointwas reached,and thus break the main circuit and close the bell or signal circuit. By the use of the distributer B, I avoid all difficulties arising from irregularities due to the varying resistance in the circuits.

In the distributer B, Ihave shown the cores and armatures of the magnets C and O as forming contacts and elements of the respective circuits in a manner well understood by electricians; but this is only for convenience, and it is within the ordinary skill of an electrician to substitute other contacts for these.

Having thus described my invention, I claim- 1. A locomotive provided with a distributer, as B, a norinally-closed electric circuit IOO including a generator and the coil, armature,

and core of one magnet, as C, of said distributer, an electric signal or bell, a normallyopen circuit including the generator, the signal-magnet, and the core and armature of the other magnet, as C, of said distributer, and a constantly-closed exciting-circuit includin g the generator, the coil of the magnet C, and an external resistance, as or, substantially as described.

2. The combination, with a railway-track provided with a contact-rail at the transmitting-point, two relays at different points along the line, a partial line-circuit including the coils of the danger-magnet D of one relay and the safety-magnet S of the other relay, said partial circuit having for its respective terminals one of the track-rails and the said contact-rail, of a locomotive provided with a distributer B, a partial electric circuit including the generator and the core, armature, and coil of magnet C of said distributer, a normally-open circuit including the generator, the core, and armature of the magnet O of the distributer, and the electric bell or signal, and a constantly-closed exciting-circuit including the generator, the coil of magnet G of the distributer, and an external resistance equal to the resistance of the longest conductor on the line.

3. The combination, with the distributer comprising the electro-magnets G and O, the vibrating armature-lever and armatures, and the resistance a, of a circuit including the generator, the coil of magnet- O and its armature and core, the signal-circuit including the generator, the signal, and the armature and core of magnet C, the constantly-closed exciting-circuit including the generator, the coil of magnet C, and the resistance '12, and the restoring-circuit including the generator, the coil of magnet O, and the switch or circuit-closer Sw, all arranged to operate substantially as set forth.

4. A locomotive provided with an electric bell or alarm, a normally-open loell-circuit including the generator, an electro-magnet C, which closes the bell-circuit, a constantlyclosed electric circuit including the generator, the coil'of said magnet, and an external resistance a, a n0r1nally-elosed electric circuit including the generator and an electromagnet C, the coil of which is included in said normally-closed circuit, said magnet 0 when excited holding the bell-circuit open and its own circuit closed, whereby, when said normally-closed circuitis broken, the bell-circuit will be instantly closed and the alarm sounded. V

In Witness whereof I have hereunto signed my name in the presence of two subscribing witnesses.

JAMES H. HUNTER. \Vitn esses:

J. W. HIGGINS, W. L. M. DESY. 

